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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Streamline-based production data integration in naturally fractured reservoirs

Al Harbi, Mishal H. 29 August 2005 (has links)
Streamline-based models have shown great potential in reconciling high resolution geologic models to production data. In this work we extend the streamline-based production data integration technique to naturally fractured reservoirs. We use a dualporosity streamline model for fracture flow simulation by treating the fracture and matrix as separate continua that are connected through a transfer function. Next, we analytically compute the sensitivities that define the relationship between the reservoir properties and the production response in fractured reservoirs. Finally, production data integration is carried out via the Generalized Travel Time inversion (GTT). We also apply the streamline-derived sensitivities in conjunction with a dual porosity finite difference simulator to combine the efficiency of the streamline approach with the versatility of the finite difference approach. This significantly broadens the applicability of the streamlinebased approach in terms of incorporating compressibility effects and complex physics. The number of reservoir parameters to be estimated is commonly orders of magnitude larger than the observation data, leading to non-uniqueness and uncertainty in reservoir parameter estimate. Such uncertainty is passed to reservoir response forecast which needs to be quantified in economic and operational risk analysis. In this work we sample parameter uncertainty using a new two-stage Markov Chain Monte Carlo (MCMC) that is very fast and overcomes much of its current limitations. The computational efficiency comes through a substantial increase in the acceptance rate during MCMC by using a fast linearized approximation to the flow simulation and the likelihood function, the critical link between the reservoir model and production data. The Gradual Deformation Method (GDM) provides a useful framework to preserve geologic structure. Current dynamic data integration methods using GDM are inefficient due to the use of numerical sensitivity calculations which limits the method to deforming two or three models at a time. In this work, we derived streamline-based analytical sensitivities for the GDM that can be obtained from a single simulation run for any number of basis models. The new Generalized Travel Time GDM (GTT-GDM) is highly efficient and achieved a performance close to regular GTT inversion while preserving the geologic structure.
62

Micro-probe for physical and chemical surface analysis /

Mathews, Joshua Benjamin, January 2001 (has links)
Thesis (M.S.) in Chemical Engineering--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 77-79).
63

Gravity drainage : microscopic studies and free fall in fractured reservoirs

Sajjadian, Valiahmad January 1999 (has links)
No description available.
64

Adsorption on porous solids of simple structure.

Ternan, M. (Marten) January 1971 (has links)
No description available.
65

The structure of the oxide/aqueous electrolyte interface

Yates, David Edwin January 1975 (has links)
The structure of the oxide/aqueous electrolyte interface has been studied. The surface porosity of several oxides to ions is evaluated and the contribution of such porosity to the double layer properties determined by surface charge measurements. The oxides studied are B.D.H. precipitated silica, before and after heat treatment, rutile, goethite, hematite and amorphous ferric oxide. The surface porosity was evaluated using nitrogen adsorption for physical porosity, tritium exchange for surface hydration and dissolution for surface crystallinity. It is found that the surfaces of metal oxides may be divided into two categories; those that are porous to ions and those that are non-porous. Of those studied only the precipitated silica and the amorphous ferric oxide are porous. The porosity is probably due to an easily permeated layer of hydrolysed oxidic material. It does lead to exceptionally high surface charges. However the non-porous oxides also exhibit high surface charges so that while surface porosity may, in some cases, contribute to oxide double layer properties, it cannot be a general explanation of the high differential capacities observed. A site-binding model for non-porous oxide/aqueous electrolyte interfaces is introduced, in which it is proposed that the adsorbed counter ions form interfacial ion pairs with discrete charged surface groups. This model is used to calculate theoretical surface charge densities and potentials at the Outer Helmholtz Plane. The calculated values are consistent with experimental data for oxides provided a high value of the inner zone capacity is accepted. An explanation is provided for the difference between silica and most other oxides in terms of the dissociation constants of the surface groups.
66

Crystal engineering of porosity /

Lloyd, Gareth Owen. January 2006 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.
67

Ultrasonic inspection of gas porosity defects in aluminium die castings

Palanisamy, Suresh. January 2006 (has links)
Thesis (PhD) - Swinburne University of Technology, Industrial Research Institute Swinburne - 2006. / A thesis submitted to the Industrial Research Institute Swinburne, Swinburne University of Technology in fulfilment of the requirements to the degree of Doctor of Philosophy, 2006. Typescript. Includes bibliographical references (p. 199-211).
68

Fine scale sandstone acidizing coreflood simulation

Li, Chunlou, Hill, A. D. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: A. Daniel Hill. Vita. Includes bibliographical references. Also available from UMI.
69

Non-Newtonian flow through porous media

Sadowski, Thomas Jefferson, January 1963 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
70

Characterization of microstructure and internal displacement field of sand using X-ray computed tomography

Razavi, Mohammad Reza, January 2006 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, December 2006. / Includes bibliographical references (p. 76-84).

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